AlGaN p-i-n ultraviolet avalanche photodiodes with suppressed surface leakage current and uniform avalanche breakdown.

We report high-performance AlGaN p-i-n ultraviolet (UV) avalanche photodiodes (APDs) based on sapphire substrates with stable breakdown voltages (V) around 113.4 V, low dark current densities (J) below 9 × 10 A/cm and a high avalanche gain over 2 × 10. A two-step deposition method was employed to reduce passivation-induced plasma damage while maintaining high dielectric film quality.

High-responsivity dual-band ultraviolet photodetector based on GaO/GaN heterostructure.

Ultraviolet photodetectors have aroused wide concern based on wide-band-gap semiconductors, such as GaN and GaO. Exploiting multi-spectral detection provides unparalleled driving force and direction for high-precision ultraviolet detection. Here we demonstrate an optimized design strategy of GaO/GaN heterostructure bi-color ultraviolet photodetector, which presents extremely high responsivity and UV-to-visible rejection ratio.

Enhanced Thermoelectric Properties of Coated Vanadium Oxynitride Nanoparticles/PEDOT:PSS Hybrid Films.

Thermoelectric (TE) materials transform thermal energy into electricity, which can play an important role for global sustainability. Conducting polymers are suitable for the preparation of flexible TE materials because of their low-cost, lightweight, flexible, and easily synthesized properties. Here, we fabricate organic-inorganic hybrids by combining vanadium oxynitride nanoparticles coated with nitrogen-doped carbon (NC@VNO) and poly(3,4-ethylenedioxy thiophene):poly(styrene sulfonate) (PEDOT:PSS).

Simulation Study on the Structure Design of p-GaN/AlGaN/GaN HEMT-Based Ultraviolet Phototransistors.

This work investigates the impacts of structural parameters on the performances of p-GaN/AlGaN/GaN HEMT-based ultraviolet (UV) phototransistors (PTs) using Silvaco Atlas. The simulation results show that a larger Al content or greater thickness for the AlGaN barrier layer can induce a higher two-dimensional electron gas (2DEG) density and produce a larger photocurrent. However, they may also lead to a larger dark current due to the incomplete depletion of the GaN channel layer.

Self-Assembly Nanopillar/Superlattice Hierarchical Structure: Boosting AlGaN Crystalline Quality and Achieving High-Performance Ultraviolet Avalanche Photodetector.

As a burgeoning wide-band gap semiconductor material, AlGaN alloy has attracted great attention for versatile applications due to its superior properties. However, its poor crystalline quality has restricted the employment of AlGaN on electronic devices for a long time. Herein, we proposed a nanopillar/superlattice hierarchical structure for AlGaN epitaxy to boost the crystalline quality.

Progress on AlGaN-based solar-blind ultraviolet photodetectors and focal plane arrays.

Solar-blind ultraviolet (UV) photodetectors (PDs) have attracted tremendous attention in the environmental, industrial, military, and biological fields. As a representative III-nitride material, AlGaN alloys have broad development prospects in the field of solar-blind detection due to their superior properties, such as tunable wide bandgaps for intrinsic UV detection. In recent decades, a variety of AlGaN-based PDs have been developed to achieve high-precision solar-blind UV detection.

Back-illuminated AlGaN heterostructure solar-blind avalanche photodiodes with one-dimensional photonic crystal filter.

AlGaN heterostructure solar-blind avalanche photodiodes (APDs) were fabricated on a double-polished AlN/sapphire template based on a separate absorption and multiplication (SAM) back-illuminated configuration. By employing AlGaN heterostructures with different Al compositions across the entire device, the SAM APD achieved an avalanche gain of over 1×10 at an operated reverse bias of 92 V and a low dark current of 0.5 nA at the onset point of breakdown.